Method of preparing barium oxid.



L. E.. SAUNDERS.- METHOD' OF PREPARING BARIUM OXID. APPLICATION FILED FEB. 5/1912.

1,1 12,721 a Patent ed 0013. 6, 1914.

W] NESSES INVENTOR,

u 1L. l M Q 1 0/ 6 Allornqys urrah snares Parana uric LEWIS n'. sannnnns, or NIAGARA FALLS, NEW YOR METHOD OF PREPARING BARIUM OXID.

iniaeei.

To aZZ whom it only concern: I

Be it known that I, Lnwis E. SAUNDERS, a citizen of the United States, residing at Niagara Falls, in the county of Niagara and State of New York, have invented certain new and useful Improvements in Methods of Preparing Barium Oxid, of which the following is a specification.

This invent-ion relates to the manufacture, in an electricor other furnace aifording suiiicient temperatures, of barium oXid or mixtures containing barium maid in available form, said. mixtures free from commercially objectionable proportions of barium sulfid or other reduction products.

Native barium sulfate, or barytes, has heretofore been reduced in the electric furnace in presence of carbon or under reducing conditions, yielding products which contain the oxid and sulfid of barium. I have discovered that under proper conditions it is possible to eliminate sulfur and oxygen from barium sulfate, usually the native sulfate, and thereby to produce barium oxid free or commercially free from barium sulfid and other reduction products. The essential con ditions are a sufficient temperature, which should be at least 1500 centigrade and referably 1000 centi 'ade or higher, an the maintenance of non-reducing conditions. It is important that no carbon or reducing gases should be. permitted in contact with the charge, as such agents result in the formation of certain percentages of barium sulfid, which it is especially desired to avoid. Any method of heating which will afford the necessary conditions may be used. A convenientmethod of working is under a reflected electric arc, care being taken that the carbon electrodes, if used, do not contact with the bath. with barium sulfate, the outer portion being water-cooled to prevent fusion.- Under these conditions product may be made containing 75% or more of barium oxid, the balance consisting chiefly of unconverted sulfate and such impurities of the original Specification of Lettersratent.

The furnace may be lined Patented Oct. 6, ion.

Application filed February 5, 1912. Serial No. 675,675.

charge as the oxide of iron, aluminum and silicon. The product is characterized bythe absence of any substantial or commercially objectionable proportion of reduction products, including barium sulfid. -The gases evolved consist mainly of sulfur trioxid, or sulfur dioxidand oxygen, or mixtures of these. The barium oxid is readily recovered from the product of the fusion by leachmg.

A furnace suitable for carrying the invention into eflect is shown in the accompanying drawing, wherein the figur. is a central vertical section.

In said figure, 1 represents the furnace shell of metal, lined with barium sulfate 5 in conjunction with a suitable binder as sodium silicate.

2 is afire-brick cover, and 3 a highly refractory reflecting surface therefor, preferably consisting of silicon carbid.

i are the carbon electrodes, maintained outof contact with the bath.

6 represents a coil of iron pipe disposed in the lining 5 and adapted for the circulation of water.

I claim I 1. The method of preparing barium oxid, which consists in heating barium sulfate to its temperature of decomposition under nonreducing conditions;

2. The method of preparing barium oxid, which consists in electrically heating barium sulfate under non-reducing conditions to its temperature of decomposition under non reducing conditions.

3. The method of preparing barium oxid, which consists in decomposing barium sulfate by the heat of an electric are maintained out of contact therewith.

.In testimony whereof I afhX my signature in presence of two witnesses.

LEWIS E. smunnns.

Witnesses Nnn. A. WVILsON, G. T. Rnrcn. 

